package/swupdate: add upstream patch to fix build with uclibc

Fix the following build failure with uclibc:

core/bootloader.c: In function 'register_bootloader':
core/bootloader.c:28:15: warning: implicit declaration of function 'reallocarray' [-Wimplicit-function-declaration]
   28 |  entry *tmp = reallocarray(available, num_available + 1, sizeof(entry));
      |               ^~~~~~~~~~~~
core/bootloader.c:28:15: warning: initialization of 'entry *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
[...]
.../arm-buildroot-linux-uclibcgnueabi/bin/ld: core/built-in.o: in function `register_bootloader':
(.text.register_bootloader+0x2c): undefined reference to `reallocarray'

Fixes:

  http://autobuild.buildroot.net/results/46dc484759549162ec246e0bff2647995c307ab5/

Signed-off-by: Ben Hutchings <ben.hutchings@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/swupdate/0001-swupdate-core-bootloader.c-fix-build-without-reallocarray.patch

@@ -0,0 +1,35 @@
+From f30c4771e93cad7e77d7f2add94327865d226553 Mon Sep 17 00:00:00 2001
+From: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+Date: Sun, 15 May 2022 14:53:35 +0200
+Subject: [PATCH] core/bootloader.c: fix build without reallocarray
+
+Use realloc instead of reallocarray to avoid the following build failure
+with uclibc raised since version 2022.05 and
+https://github.com/sbabic/swupdate/commit/b8897ed695e1cd954859142b14ec8546d2e7994a:
+
+microblaze-buildroot-linux-uclibc/bin/ld: core/built-in.o: in function `register_bootloader':
+(.text.register_bootloader+0x30): undefined reference to `reallocarray'
+
+Fixes:
+ - http://autobuild.buildroot.org/results/7208e8189b4a6f35aaa4ed7777ecdd37421a7c7f
+
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+Backported from: f30c4771e93cad7e77d7f2add94327865d226553
+Signed-off-by: Ben Hutchings <ben.hutchings@mind.be>
+---
+ core/bootloader.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/core/bootloader.c b/core/bootloader.c
+index f34cb414..5694d43d 100644
+--- a/core/bootloader.c
++++ b/core/bootloader.c
+@@ -25,7 +25,7 @@ static unsigned int num_available = 0;
+ 
+ int register_bootloader(const char *name, bootloader *bl)
+ {
+-	entry *tmp = reallocarray(available, num_available + 1, sizeof(entry));
++	entry *tmp = realloc(available, (num_available + 1) * sizeof(entry));
+ 	if (!tmp) {
+ 		return -ENOMEM;
+ 	}